When analyzing a source, historian has to remain unbiased and free from personal feelings and opinions. They know that there are different source of an event and they may reveal different facts which could cross-check his argument. The objective historiography is possible only when the historian is unbiased and when different sources like archaeological, literary and other sources are cross-checked and interpreted independently.
The King and the pope led the two hierarchies that formed the cornerstone of
feudalism. Sometimes these two figures worked together but sometimes they clashed.
This is definitely false. Gymnosperms do use seeds but are exposed like the pine cones of pines. Angiosperms still have seeds, however, they flower or fruit (which can are seeds).
Kepler did multiple things, but his most famous work is demonstrating that the planets move in an elliptical (kind of like an oval) orbit around the sun instead of a circular orbit.
